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Mydata A12 tool tip damage

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We keep seeing a problem with the plastic tool tip on an A12... - Jul 17, 2007 by Peter Allgood  

#51074

Mydata A12 tool tip damage | 17 July, 2007

We keep seeing a problem with the plastic tool tip on an A12 tool being sliced off. I think it is hitting the edge of the tape separator clip assembly - I determined this by coating the tip in paint and then finding where the tip had struck the metalwork and left a chip of paint behind. I visualise the fault as the head not settling completely in the x axis before it starts down to pick the part and thus occasionally it strikes the edge of the separator. I have tried slowing head accelerations right down but its still doing it. UK cost of this silly bit of plastic is about $40! And I can go through them every few hundred parts at times.

All ideas very gratefully received.

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#51078

Mydata A12 tool tip damage | 17 July, 2007

Is your machine a TP9 2U ?

If you have a UFP or a MY series machine this condition usually points towards a bad X-wagon motor.

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#51088

Mydata A12 tool tip damage | 18 July, 2007

Thank you for the reply - and yes its a TP9-UFP! Problem doesnt happen all the time and may not happen for extended periods on the job where we see it most - this particular job uses all feeder slots so the head is whizzing back and forth quite a lot - we can typically process several panels (qpprox 700 passives on each) then we'll get a tip strike. We may then get several in succession or we might go for many more panels before it happens again.

I wondered if its a time related problem - ie the machine has been running for a while and something is losing accuracy - I did wonder if there was any kind of encoder on the x motor that might be wearing out.

Apart from changing out the motor, do you have any suggestions for reducing the problem? I wondered about the validity of reinitialising the system at intervals to reset any axis errors.

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#51089

Mydata A12 tool tip damage | 18 July, 2007

I was asking if it was a TP9 2U......

If you have a UFP machine then you are in luck. It is most likely the small X-motor. You can test it in the service program. Does the X-axis bounce when you are trimming magazines and stepping through placements ?

If you have a TP9 2U then you might be in trouble. We had an issue like you described that we could not resolve.

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#51090

Mydata A12 tool tip damage | 18 July, 2007

Sorry I misunderstood, its a UFP. And yes it does wobble as you step from slot to slot and when you step through a pcb, not a huge wobble, more of a shimmy really.

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#51091

Mydata A12 tool tip damage | 18 July, 2007

Bad small X motor most likely.

Other possibilities: Bad cables Bad Card

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#51092

Mydata A12 tool tip damage | 18 July, 2007

OK thanks - I wasnt aware that I HAD a small x motor! You mentioned being able to check in the service menu - would you care to point me in the right direction.

What amazes me - or rather, worries me, is that repeated mentions to the Mydata service engineer have only resulted with me being told that they dont know why its doing it!

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#51094

Mydata A12 tool tip damage | 18 July, 2007

send me an e-mail and I will give you the test procedure.

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#51102

Mydata A12 tool tip damage | 19 July, 2007

You dont mention if it is ONLY occuring with the A12 or is it other tools as well? Only spring tools or Stiff ones?

Regardless of that, the small X Wagon motor is controlled by the track ball and the bigger X Axis motor is controlled by the joystick on the end panel of the machine.

The Joystick which controls the big motor is a course resolution motor, meaning it will appear jerky when its positioning since it is moving for example .... 100 pulses per inch. Where as the smaller X Axis positiong (pancake)motor may have 1000 lines of resolution per inch of movement.... hence more accuracy and smoother linear movement.

What I have found to destroy tools tips faster than anything is when we are running a job with more magazines than positions on the machine and we are swapping mags on the fly. When the operator swaps out the magazine and doesnt trim it manually but rather lets the machine find the fids on its own, there have been instances where the machine recognizes the WRONG position on the mag. This results in the machine referencing itself incorrectly and then ends up trying to pick from the metal seperators rather than the pick positions. This will eat a tip in a heartbeat and sometimes bend the tool shaft.

Good luck in figuring out your problem!

Chris

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#51105

Mydata A12 tool tip damage | 19 July, 2007

Hi

Thanks for the input. Problem is only ever the A12 plastic tip (no damage ever seen on any other tool). I suspect we have not helped by skipping the retrim operation when we have changed a part so we'll do that but also I just discovered setting in the utility menus for x axis overshoot - variable between 0 and 5mm - presently set to 5mm. Does that have a bearing on the wobble?

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#51106

Mydata A12 tool tip damage | 19 July, 2007

Chris, Are you sure about the joystick trackball statement?

He said he is seing "bounce" when he steps through placements and when he trims mag positions. That would indicate a issue with the small x-mot system to me.

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#51107

Mydata A12 tool tip damage | 19 July, 2007

Peter, GO TEST YOUR SMALL X-MOTOR IN THE SERVICE PROGRAM !!!!!!

Do not start changing parameter files ! I assume that your machine worked fine at one time with the original parameter file.

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#51109

Mydata A12 tool tip damage | 19 July, 2007

Ok I can get into the service program - under Motors there is only a single X motor listed. And what test can you do - seems that I can only display ranges and settings? No test as such?

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#51129

Mydata A12 tool tip damage | 19 July, 2007

You might want to check the Xwagon bearings. We had the same issue with the TP9-UFP we ordered all the possible parts Xmotors small large, encoder, transducer, couplings etc. over 10K worth of parts. The only thing we didnt order was the actual x-wagon bearings and that my friend was the problem. Maybe your service guy could check the bearings for you before you order any big money parts. I hope this helps and good luck

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#51133

Mydata A12 tool tip damage | 20 July, 2007

Yes that sounds worth a look - thanks.

I am also wondering if there is a thermal issue - we had 27 degrees in here yesterday and I remember the Mydata guy telling me to put a desk fan onto the card frame in the summer. I did this last year - when I didnt have much of a problem so maybe it is linked. Also the problem I think only occurs after the machine has been running for a few hours and everything has warmed up I suppose.

To all posters on the thread I am away for a week now so wont be able to reply to anyone but any other help or suggestions will be gratefully received and I will act upon it when I get back.

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#51134

Mydata A12 tool tip damage | 20 July, 2007

Sr. Tech, youre absolutely correct that the X-Wagon (pancake) motor is the one which will do final positioning when moving to a programmed position. The X Axis motor in back of the machine is used for rapid traverse of the axis.

I was thinking more about this yesterday after I posted and I got to thinking that it may not be a bad idea to try swapping the MOT-X card with say the MOT-Y card. Just be sure to plug in the ribbon cable when re-installing the card in the rack.

After reading that they are operating in 80 degree F heat in their plant. You can add 10 more degrees F in the card cage. Add 20 or more if the rear filters are dirty or the fans under neath the card cage are full of lint.

if the fans in the rear get too dirty and do not allow air to pass into the machine the small fans under the card cage WILL pull dirt and lint off the floors and clog the cooling vents in the card cage and also plug up the bottom of the ELMO unit causing it to overheat and when that happens the power resistor in the bottom of the ELMO will blow up inside its heat sink (learned this the hard way).

We clean the card cages fans and cage itself annually now. This entails removing every card, Elmo power supply and blowing the cage out, vacuuming the foam under the cage inside the machine, cleaning the circulation fans under the cage housing and the main intake fans in the rear of the machine. Cooling of these machines is very important for repeatability and consistant operation without failure. We have halfed our annual downtime by doing these simple tasks.

Chris

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#51135

Mydata A12 tool tip damage | 20 July, 2007

If you still have trouble with this problem try calling MyData and ask their opinion. I know this sounds simple and maybe you have tried already, but I have found in the past that there are certain techs who really know their stuff.

Glen Gayton in Boston and Wes Shoemaker in California are two who are extremely helpful! gaytons number is 1-978-948-7378 and Wes's number is 1-167-571-2930. If unable to reach either of those two for whatever reason, Matt Stott the National Service Manager is available at 1-978-697-0438.

They are all factory trained and really good and helpful! Good luck!

Chris

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#51137

Mydata A12 tool tip damage | 20 July, 2007

Well yesterday was uncharacteristically warm for a British summer! I always have the panel off the end of the machine at all times and certainly used to have a large desk fan blowing into it - for some reason I stopped.

I had a run of strikes yesterday afternoon so I shut down with a board half placed. This morning (22 degrees) I continued running the program from where it left off and no strike although I couldnt then run any more work through to prove the point.

I checked the wobble on step through immediately I switched on and a hour or two later - no difference: when stepping along a horizontal row of parts (eg x axis only) you see the camera apparently overshoot the position then pull back onto it and stop. I must stress though that thsi is incredibly quick and the amount of overshoot is tiny, its almost like you cant see it, ist that small but definitely something.

I too have been thinking what various people have said and think that things like worn bearings would give me the fault all the time, this definitely seems to be time related - there could be other factors that I have failed to isolate yet of course.

We build this job in batches of 10 panels a day - each with 700 placements. This happens in background mode - the machine may be switched on all day and another panel loaded when we remember! Usually we get through 7-8 panels before we get a tip strike then we'll get several in succession. At that point we have finished the days work and off goes the machine until the next day. When I get back from vacation I will try blasting a fan through the card cage. I am due a service visit so maybe that will show something up as well.

Thanks again everyone!

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